Silica fume, also known as microsilica, is a byproduct of the reduction ... purity quartz with coal in electric furnaces. 1. Introduction:Silica fume is a byproduct of producing silicon metal or ferrosilicon alloys ... raw materials are quartz, coal, and woodchips.2. Usage:Silica fume can still be used in the production of refractory and ... , re-use is allowed after drying and crushing. Silica Fume